That error suggests that all of these events have occurred on your site:
You have the module “stories” enabled.
You have at least one story created
The text you searched for exists only in one “story”
That story is not linked to any individual, or at least not to any individual that can be displayed (due to privacy)
Can you please confirm each of these points. Then I can provide a solution.
If you are not sure of an answer, please send me admin access to your family tree so I can review the fault, and tell me what you searched for.